1. Field of the Invention
The present invention relates to a knee protecting airbag device capable of protecting the knees of an occupant such as a driver or an occupant on an assistant seat with an airbag, which is expanded and inflated by introducing an inflating gas.
2. Description of Related Art
In the related art, a device for protecting the knees of an occupant such as a driver is constructed to include: an airbag folded so that it can be expanded and inflated toward the front side of the knees of the seated occupant; an inflator for providing the airbag with an inflating gas; and a case for accommodating and holding the folded airbag and the inflator (as referred to JP 2003-118528A, for example).
In the knee protecting airbag device of the related art, however, an inflator of a generally column-shaped cylinder type is arranged together with the airbag in the case. This arrangement makes it difficult to house the folded airbag without clearance in a space around the inflator. For example, the airbag is hard to enter the clearance in the case on the front side of the inflator. There is room for improvement in the point that the space in the case is effectively utilized.
If, in this case, the construction is modified such that only the airbag is accommodated in the case by arranging the inflator outside of the case, the flexible airbag can be accommodated so far as the corners of the case. Therefore, the space in the case can be effectively utilized to make the case compact.
In case, however, the inflator is arranged outside of the case, it is necessary to guide the inflating gas into the airbag without any gas leakage.
Further, in another knee protecting airbag device of the related art, a folded airbag and an inflator are accommodated in a case opened on the vehicular rear side, and airbag cover is arranged to cover the case opening on the vehicular rear side (as referred to JP-A-2003-267178, for example).
However, the knee protecting airbag device of the related art is so mounted on the vehicle that the case accommodating the folded airbag and the inflator is fixed at its predetermined portion on the vehicular body side while assembling an airbag cover integrally with the case. When the case is mounted and fixed on the body side, therefore, the mounting works have to be done at the portion, where the worker finds it hard to view, such as the back or the side of the case, so that the mounting workability is not excellent. Especially in the knee protecting airbag device of the related art, after an instrument panel as an interior component arranged around the airbag cover was attached to the body side, the integrated airbag device is fixed on the body side. This makes the working space small at the mounting work and makes it difficult to observe the mount portion of the case on the body side. Therefore, the knee protecting airbag device of the related art cannot have a satisfactory workability for the mounting operation.